All-Nanochitin-Derived, Super-Compressible, Elastic, and Robust Carbon Honeycombs and Their Pressure-Sensing Properties over an Ultrawide Temperature Range.

Elastic carbon aerogels show great potential for various applications but are often hindered by structure-derived fatigue failure, weak elasticity with low compressibility, and low stress and height retention. Herein, we demonstrate a super-elastic and fatigue-resistant nanochitin-derived carbon honeycomb with honeycomb-like anisotropic microstructures and carbon-based molecular structures, which was tailored by optimizing the nanochitin concentrations and carbonization temperatures. The carbon honeycomb fabricated at a nanochitin concentration of 1.0 wt % and a carbonization temperature of 900 °C demonstrated anisotropic honeycomb channels, nanofibrous network channel walls with few cracks, and weak interactions between the carbonized nanochitin, which afforded high compressibility with up to 90% strain and complete recovery. In particular, the carbon honeycomb provided good fatigue resistance with high stress and height retentions of 87 and 94%, respectively, after more than 10,000 compression cycles at 90% strain. Moreover, the tailored anisotropic honeycomb channels and molecular structures endowed the carbon honeycomb with elasticity even under severe conditions, such as exposure to flame (approximately 1000 °C) and liquid nitrogen (approximately -196 °C). Owing to these properties, the nanochitin-derived carbon honeycomb could act as a high-sensitivity pressure sensor for a wide working pressure range of 0-185.5 kPa and ultrawide temperature range of -196-600 °C. This study can provide a promising route to develop all-biomass-derived, super-elastic, and fatigue-resistant carbon materials for pressure sensing under harsh conditions and for versatile electronic applications.